SCN4A and dilated cardiomyopathy: Neutralization of these amino acids in other voltage-gated ion channels has been linked to diseases, such as hypokalemic periodic paralysis (Nav1.4 [29] or Cav1.1 [30]), normokalemic periodic paralysis (Nav1.4 [31] or Cav1.1 [32]), mixed arrhythmias associated with dilated cardiomyopathy (Nav1.5 [33]) and peripheral nerve hyperexcitability (Kv7.2 [34]).